196 THE GREEK ASTRONOMY. 



the time. And thus the problem of the resolution 

 of the celestial motions into equable circular ones, 

 which was propounded above two thousand years 

 ago in the school of Plato, is still the great object 

 of the study of modern astronomers, whether ob- 

 servers or calculators. 



That Hipparchus should have succeeded in the 

 first great steps of this resolution for the sun and 

 moon, and should have seen its applicability in 

 other cases, is a circumstance which gives him one 

 of the most distinguished places in the roll of great 

 astronomers. As to the charges or the sneers 

 against the complexity of his system, to which we 

 have referred, it is easy to see that they are of no 

 force. As a system of calculation, his is not only 

 good, but, as we have just said, in many cases no 

 better has yet been discovered. If, when the actual 

 motions of the heavens are calculated in the best 

 possible way, the process is complex and difficult, 

 and if we are discontented at this, nature, and not 

 the astronomer, must be the object of our dis- 

 pleasure. This plea of the astronomers must be 

 allowed to be reasonable. " We must not be re- 

 pelled," says Ptolemy 12 , "by the complexity of the 

 hypotheses, but explain the phenomena as well as 

 we can. If the hypotheses satisfy each apparent 

 inequality separately, the combination of them will 

 represent the truth; and why should it appear 

 wonderful to any that such a complexity should 

 12 Synt. xiii. 2. 



